The increase of broadcasting services coming from terrestrial, cable, and satellite broadcasting resulted in diversified broadcasting channels, allowing viewers to enjoy abundant video contents.
As the video contents become abundant, overlapping of broadcasting time of popular programs frequently happens; in this case, to watch a broadcasting program that the viewer wants to watch while avoiding advertisements as possibly as he or she can, the viewer may more or less repeat switching between a current channel and a channel where the broadcasting program the viewer wants to watch is broadcast.
Although broadcasting signals are provided in such a way that EPG (Electronic Program Guide) information is included therein as broadcasting services are being digitalized, it is not uncommon the EPG information provides incorrect program start time; therefore, even if the viewer switches channels based on the EPG information, it is likely that a broadcasting program wanted has not started yet on a switched channel. In this case, the viewer may again repeat the channel switching more or less while watching the program broadcast on the previous channel.
The viewer, to avoid the tedious channel switching, may display a broadcasting program of a target channel to which the viewer wants to switch after a while together with a broadcasting program that the viewer is currently watching in the form of a main screen 1a and an auxiliary window 1b as shown in FIG. 1, thereby continuously checking the start of the broadcasting program in the target channel. Since a part 1b of a currently watched video 1c is continuously occupied by the broadcasting program from another video channel in a PIP (Picture in Picture) type display as shown in FIG. 1, the viewer may feel uncomfortable due to the blocking video zone.